On that momentous day of July 20, 1969, Armstrong and Buzz Aldrin walked on the Moon’s surface for three hours, collecting rock samples, taking photographs and conducting experiments. From the AP obit:

“The sights were simply magnificent, beyond any visual experience that I had ever been exposed to,” Armstrong once said.

The moonwalk marked America’s victory in the Cold War space race that began Oct. 4, 1957, with the launch of the Soviet Union’s Sputnik 1, a 184-pound satellite that sent shock waves around the world.

Although he had been a Navy fighter pilot, a test pilot for NASA’s forerunner and an astronaut, Armstrong never allowed himself to be caught up in the celebrity and glamor of the space program.

“I am, and ever will be, a white socks, pocket protector, nerdy engineer,” he said in February 2000 in one of his rare public appearances. “And I take a substantial amount of pride in the accomplishments of my profession.”

Armstrong was born in Wapakoneta, Ohio, and from a young age was fascinated with aviation, experimenting with model airplanes and a home-built wind tunnel. At 15 he began flying lessons in an Aeronca Champion, and by 16 acquired his student pilot’s licence. In 1947, he enrolled at Purdue University on a Navy scholarship to pursue a degree in aeronautical engineering, but in 1949 the Navy called him to active duty in the Korean War. As a navy pilot, he flew 78 combat missions. He was shot down once and received three medals for his military service. In 1952 he returned to his studies and completed his BSc at Purdue and an MSc in aerospace engineering at the University of Southern California.

In 1955 he became a civilian research pilot at the Lewis research centre of the National Advisory Committee for Aeronautics (Naca), the forerunner of the National Aeronautics and Space Administration (Nasa). Later that year, he transferred to Naca’s high-speed flight station (today, Nasa’s Dryden flight research centre) at Edwards Air Force Base in California as an aeronautical research scientist, and then as a pilot. He was a test pilot on many pioneering high-speed aircraft, including the 4,000mph X-15. He flew over 200 different models of aircraft, including jets, rockets, helicopters and gliders.

Armstrong was engaged in both piloting and engineering aspects of the X-15 programme from its inception. He completed the first flight in the aircraft equipped with a new self-adaptive flight control system and made seven flights in the rocket plane. In 1962 he was of the nine test pilots chosen by Nasa for its second astronaut-training programme.

Here’s a round-up of some of the reactions from the Twitterverse — :

A flash of some of the reactions as the space community reacts to news of Armstrong’s death

Armstrong’s reticence to make public appearances or give interviews means that, for many Americans, their sole memory of Armstrong was his trip to the moon. On a related note, it also made his autograph one of the most valuable in the memorabilia market, ahead of Queen Elizabeth II, Paul McCartney and Muhammad Ali. In 2010, our sister publication Air and Space‘s Mike Klesius reported:

According to his biography, signed anything he was asked to for the first fifteen or so years after the moon landing. Then, dealers of collectibles began misrepresenting themselves as school teachers or children, asking for signed photos by mail. By 1993, Armstrong saw that forgeries of his signature were being sold on the Internet, and stopped giving his autograph, advice that Charles Lindbergh had given him in September 1969 at a banquet of the Society of Experimental Test Pilots.

Nonetheless, Armstrong’s autograph, according to Paul Fraser Collectibles of the United Kingdom, is the most valuable in the world, and fetches more than $7,500 these days

In 2010, Owen Edwards wrote in Smithsonian about the model of the Eagle lunar lander, on view at the National Air and Space Museum on the Mall:

Today, visitors to the Apollo exhibition witness an artifact that looks—with a little help from artful curators—much as Eagle looked when it made that giant leap 40 years ago. When Buzz Aldrin radioed back to us riveted earthlings that “this stands as a symbol of the insatiable curiosity of all mankind to explore the unknown,” he was talking about the overall mission. But he might as easily have been referring to the ungainly marvel that made it possible.

This weekend, the lander module, the Apollo to the Moon gallery and the Apollo 11 capsule would be a good place to start to pay tribute to the American icon.

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